The aim of this project is to identify the means by which human observers organize moving structures and perceive them as dynamic wholes. The particular moving structures used will be computer-generated displays of dots that, in their movement, mimic human walkers, rolling wheels, and other everyday events. Previous research has shown that these displays yield robust percepts, despite their relative impoverishment of seen elements. And the dearth of elements involved allows simple and concise mathematical description. This project will proceed on three fronts. The first will study perceptual organization with a particular focus on how much time is needed to organize a dynamic stimulus. Brief displays of systems of dots will be displayed for varying amounts of time in order to assess the durations necessary for the identification of familiar movements of near-familiar objects. The second will study perceptual organization with a focus on the effectiveness of various kinds of camouflage in inhibiting identification of common objects in motion. Static and dynamic camouflages of several types will be employed, with a particular emphasis on the movement parameters of a dynamic camouflage that are most effective in interfering with identification. The third will study perception organization with a focus on the information available about movement in iconic memory. Previous research has shown that such information is available, and the nature of the coded form of that information will be assessed. The idea is that if information about many parameters of movement is available as early as the icon, then the perceiver is clearly attuned to that information and appears not to need to elaborate it in a computational fashion. The disciplines involved in this study are, primarily, psychology and visual perception, and, secondarily, artificial intelligence and computer simulation. The health relatedness of this project is to be measured in terms of understanding the normal function of the human visual/perceptual system, both in situations of natural complexity and in reduced complexity such as when viewing elements on radar screens, and when watching for pedestrians crossing the streets at night.